Is infection causing overcarbonation?

[WelshPaul]

Hi guys,
I recently had to throw away 40 bottles of stout that had obviously picked something up which made it bitter and undrinkable. However, another effect seemed to be making the beer ludicrously bubbly, so that bottles had to be opened in the sink and left to stand while half of their volume bubbled out. Annoying but no massive loss.

Now, I've heard some people say that certain unwanted reactions can cause this kind of behaviour and I'm very concerned as my recently bottled Tripel is showing extreme levels of carbonation when I tested a bottle this weekend. It was bottled on 28th February.
To both the Tripel and the Stout I added approximately 5g of caster sugar per litre when bottling, although the Tripel was around the 8°C mark when bottled, so may have contained more CO2 than I had accounted for.
Can anyone offer suggestions for these two instances of overcarbonation and help to set my mind at ease?

 

[PD]

5 gms of sugar per litre is high. Its up in the fizzy lager levels.
Stouts and ales in my opinion do not need that level of carbonation ( although I did a coopers dark ale once and it came out like alcoholic dandelion and burdock...quite nice. )
Stick to around 3 gms of sugar for stouts and beers.

 

[WelshPaul]

Fair enough - I'm wondering then if the Tripel has simply been overcarbonated since it was bottled at pretty low temperatures.
I usually use the guide below to work out the required levels of sugar so I'm wondering why carbonation is so high on this one.

http://byo.com/resources/carbonation

 

[Dunfie]

A wild yeast infection can cause over carbonation. The wild yeast can work on the sugars that the brewing yeast doesn't.

Often you get a foaming in the mouth rather than a a full blown gusher.

 

[PD]

That's a bit complicated for me !

stick to 3gms of sugar for beers 5 for fizzy lagers.....

I never was good at maths....

I'm not ruling out any infection but if you have taken care it should not be a problem

 

[WelshPaul]

A wild yeast infection can cause over carbonation. The wild yeast can work on the sugars that the brewing yeast doesn't.

Often you get a foaming in the mouth rather than a a full blown gusher.

Well, I think I'll have to video the next test bottle that I open next month as the last one went off like a rocket! Tasted OK once it settled though.